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Efficient Attention-Sharing Information Distillation Transformer for Lightweight Single Image Super-Resolution
No full textTransformer-based Super-Resolution (SR) methods have demonstrated superior performance compared to convolutional neural network (CNN)-based SR approaches due to their capability to capture long-range dependencies. However, their high computational complexity necessitates the development of lightweight approaches for practical use. To address this challenge, we propose the Attention-Sharing Information Distillation (ASID) network, a lightweight SR network that integrates attention-sharing and an information distillation structure specifically designed for Transformer-based SR methods. We modify the information distillation scheme, originally designed for efficient CNN operations, to reduce the computational load of stacked self-attention layers, effectively addressing the efficiency bottleneck. Additionally, we introduce attention-sharing across blocks to further minimize the computational cost of self-attention operations. By combining these strategies, ASID achieves competitive performance with existing SR methods while requiring only around 300K parameters - significantly fewer than existing CNN-based and Transformer-based SR models. Furthermore, ASID outperforms state-of-the-art SR methods when the number of parameters is matched, demonstrating its efficiency and effectiveness
ReD shoes: actuated footwear for multisensory redirected walking in virtual reality
No full textA major challenge in virtual reality (VR) is enabling users to navigate expansive virtual environments within confined real-world spaces. Although redirected walking (RDW) addresses this by manipulating users' walking paths, it is hindered by visual-vestibular inconsistencies, leading to reduced immersion, discomfort, and constrained detection thresholds (DTs). We introduce ReD Shoes, redirecting shoes for VR locomotion with dynamically adjustable inclination designed to enhance multisensory integration by providing haptic feedback directly to the feet. This feedback mitigates visual-vestibular inconsistencies by enhancing proprioceptive cues and aligning tactile sensations with visual stimuli, thereby improving self-motion perception, presence, and gait stability. We conducted two experiments with 30 participants: 10 in a pilot study to optimize inclination parameters and 20 in a main study to evaluate the DT, gait stability, and user experience under No Inclination, Low Inclination (1 cm), and High Inclination (1.5 cm) conditions. Low Inclination considerably expanded the DT (43.64%), enhanced the user's feel of presence, and maintained walking stability through effective multisensory alignment. In comparison, High Inclination showed a smaller DT expansion (33.86%), increased discomfort, reduced stability, and aggravated oculomotor symptoms due to intensified sensory conflicts. This study demonstrates the use of ReD Shoes in addressing key RDW limitations by enhancing DT, stability, and user presence through active haptic feedback. Our findings offer insights for developing advanced VR mobility solutions, supporting adaptive haptic footwear that improves RDW functionality and extends immersive VR applications in gaming, training, and rehabilitation.TRUEsciescopu
Electrolyte with solvent−dominant solvation structure by complex hydride for Li−S batteries
No full textLithium−sulfur (Li−S) batteries are considered promising next-generation energy storage systems due to their high energy density, low-cost S cathodes, and potential for sustainable large-scale applications. However, they face significant challenges, including the lithium polysulfides (LiPS) shuttle effect associated with the S cathodes and interfacial reactions at the Li metal anodes, which occur concurrently and hinder their stable operation. To address these simultaneous issues at both the cathode and anode, we propose the use of complex hydrides as an electrolyte additive. Closo-type complex hydride Li(CB11H12) dissociates in the electrolyte to form mobile lithium cations and rigid polyanionic complex anions [CB11H12]−, which form Li+−solvent coordination by pushing anions outward by its weak coordinating ability. The weakened solvation free energy and the reducing ability of this modified electrolyte suppress LiPS dissolution at the S cathode as well as facilitates stable lithium anode reaction, enhancing the cycling stability and coulombic efficiency of Li−S batteries. The findings of this study underscore the importance of designing electrolyte structures using various complex hydrides and highlight their potential to address the limitations of Li−S batteries, paving the way for future advancements in this field.Master1. Introduction 1
1.1. Lithium−sulfur batteries 1
1.2. Electrolyte research for Li−S batteries 2
1.3. Complex hydride for solid electrolytes 3
1.4. Research subjects 4
2. Experimental 5
2.1. Solvation-structure engineering of electrolytes 5
2.1.1. Preparation of CNT-based S cathodes 5
2.1.2. Preparation of Carbon-coated separator 5
2.1.3. Preparation of electrolyte 5
2.1.4. Electrochemical measurements 6
2.1.5. Material characterization 6
3. Result and discussion 7
3.1. Electrolyte synthesis and solvation structure 7
3.1.1. Characteristic of complex hydride 7
3.1.2. Electrolyte composition and preparation 7
3.1.3. Analysis of solvation structure 11
3.2. Evaluation of LiPS solubility 15
3.2.1. Solvation-dependent thermodynamic voltage profiles 15
3.3. Electrochemical performance using complex hydride-based electrolyte 17
3.3.1. Electrochemical performance of Li−S full cells 17
3.3.2. Behavior of lithium metal anodes 23
3.4. Analysis of the electrode interface and morphology 26
3.4.1. Structural characterizations of the Li metal anodes during cycling 26
4. Conclusion 29
5. References 30
6. 감사의 글 3
Theoretical Analysis of AI Legal Policy
No full text유럽연합 및 한국 인공지능법 제정 이후 인공지능 정책에 대한 관심이 날로 급 증하고 있다 그러나 그러한 양적 성장에도 불구하고 이러한 관심은 산업의 혁신과 규제 완화라는 파편화된 부분적 이해에만 그치는 것이 일반적 경향이다 이는 무엇보다도 인공지능 나아가 과학기술 정책이 전체를 포괄하는 이론적 논의보다는 세간의 이목을 끈 몇 가지 사례에 집중하여 임시변통으로 대처한 데서 비롯된 현상이다. 이와 같은 상황이 반복된다면 추후 인공지능 이후 또 다른 신기술이 부상하였을 때 그동안 거둔 모든 성과를 원점으로 돌리고 사례에 입각한 각개격파식 정책을 수립 할 위험이 크다.
이러한 문제의식에서 본고는 실무에 유의미한 시사점을 줄 수 있을 만한 적절한 추상성과 구체성의 정도를 조율하여 인공지능 정책의 이론적 고찰을 시도하였다. 이 작업의 출발점으로 본고에서는 인공지능 정책과 유관 개념의 연혁적 발전사를 조망하면서 그 차이를 명확히 구분하였다 이어서 인공지능 정책이 나아가야 할 방향을 제시하기 위해 로위의 이론을 매개로 삼아 정책 개념의 네 가지 하위 목표를 도출하였다 끝으로 국내의 인공지능 법안 논의에 적용하여 한국의 인공지능 정책이 로위의 이론 중 일부에만 주목하여 다른 중요한 가치를 누락하고 있음을 확인하였 다 향후의 인공지능 정책은 이와 같은 한계를 극복한 유기적이고 종합적인 방향을 향해 나아갈 필요가 있다는 것이 본고의 결론이다.FALSEothe
Warm Arctic-Cold Continents trajectory under global warming and impacts of aerosol-induced atmospheric circulation changes on sea ice
No full textThe Arctic region is experiencing unprecedented warming at nearly four times the global average rate, which drives significant changes in global atmospheric circulation patterns and extreme weather events, profoundly impacting human societies and ecosystems worldwide. This dissertation aims to investigates the complex interplay between Arctic warming, anthropogenic forcings, and their impacts on regional weather patterns, employing statistical techniques and climate model ensemble analysis. The research reveals three key findings. First, it is demonstrated that while the Warm Arctic-Cold Continents (WACC) pattern persists under 1.5°C and 2.0°C warming scenarios, increased variability in East Asian temperature responses complicates prediction accuracy. Second, CESM1 large ensemble simulations reveal that WACC frequency peaks around 2020 before declining—beginning around 2024 for East Asia and 2039 for North America—coinciding with a northward shift of Arctic cold air boundaries as global warming restricts polar air intrusion. Third, this study shows that anthropogenic aerosols paradoxically contribute to sea ice reduction in the western Chukchi Sea by modifying North Pacific circulation patterns, enhancing northward surface stress in the Bering Strait. This mechanism, acting in concert with greenhouse gas forcing, creates a dipole circulation pattern that accelerates sea ice loss beyond what would be expected from greenhouse gases alone. These findings advance our understanding of Arctic climate dynamics and their global teleconnections, providing insights into the evolution of the WACC pattern and unexpected influence of anthropogenic aerosols on Arctic-midlatitude teleconnection.DoctorAbstract i
LIST OF FIGURES iv
LIST OF TABLES vi
I. Introduction １
1.1. Research Background and Motivation １
1.2. Objective and Overview ５
1.3. Literature Review ６
1.3.1. Arctic amplification ６
1.3.2. Warm Arctic-Cold Continent (WACC) １２
1.3.3. Observational analysis versus modeling １７
II. Investigating Changes in WACC due to Global Warming ２１
2.1. Introduction ２１
2.2. Data and Methods ２２
2.2.1. Data ２２
2.2.2. Regression analysis ２３
2.2.3. Granger causality analysis ２４
2.3. Results ２６
2.3.1. Arctic-midlatitude relationships in observations ２６
2.3.2. Global warming impacts on Arctic-midlatitude relationships ２９
2.3.3. Atmospheric circulations related to Arctic-midlatitude teleconnection ３３
2.3.4. Process of the Arctic-midlatitude teleconnection ３７
2.4. Discussion ４０
III. Potential Timeline of WACC ４２
3.1. Introduction ４２
3.2. Data and Methods ４３
3.2.1. CESM1 large ensemble community project (LENS) ４３
3.2.2. Defining warm/cold frequency and identifying onset of declines ４４
3.3. Results ４６
3.3.1. Potential timeline of warm Arctic cold continent days ４６
3.3.2. Northward shift of Arctic cold air boundaries in a warming climate ５４
3.4. Discussion ５６
IV. Identifying the Effects of Anthropogenic Aerosols on Sea Ice Loss ５８
4.1. Introduction ５８
4.2. Data and Methods ５９
4.2.1. Data ５９
4.2.2. Statistic ６３
4.2.3. Analysis approach ６４
4.3. Results ６５
4.3.1. Arctic sea ice trends and associated circulation changes ６５
4.3.2. Linear and nonlinear components of Arctic change ７３
4.3.3. Temporal changes in Bering Strait surface stress and western Chukchi Sea conditions . ７６
4.3.4. Relationship between Bering strait surface stress and western Chukchi sea ice ７９
4.4. Discussion ８１
V. Summary and Conclusion ８３
VI. REFERENCE ８５
Acknowledgments １００
Curriculum Vitae １０
A hybrid fault diagnostic approach using operational transfer path analysis and denoising deep learning with remote sensors: Application to electric vehicles
No full textThis study proposes a new approach to diagnose drivetrain faults in electric vehicles through the use of remote sensors placed under the driver's seat. The research aims to address the reduction in diagnostic accuracy caused by the receiver's lower sensitivity when diagnosing faults in the drivetrain (source) located far from the receiver. The proposed approach builds on transfer path analysis (TPA), identifying critical paths between the source, transition locations, and receiver. A denoising deep learning model is proposed for operational TPA (OTPA) to overcome the limitation of conventional TPA methods, such as singular value decomposition. The denoising deep learning model takes the vibration signal captured at the receiver location and converts it through the transition locations into the vibration signal that is intended to closely represent the original vibration signal from the source location. Finally, a diagnostic deep learning model classifies drivetrain faults using the synthetic vibration signals from OTPA. The experimental results of real-scale electric vehicles show that the proposed approach effectively diagnoses the electric vehicle drivetrain faults using remote sensors. © 2025 Elsevier LtdFALSEsciescopu
Restoring the glioblastoma tumor microenvironment by targeting C5a with the antagonist W54011
No full textGlioblastoma (GBM) poses a serious challenge due to its aggressive nature and poor prognosis. Tumor mesenchymal stem-like cells (tMSLCs) secrete complement component 5a (C5a), altering the tumor microenvironment (TME) and promoting tumor progression. This study investigated W54011, a C5a antagonist, to counteract C5a-induced malignancy in GBM tumorspheres. We assessed GBM tissues for C5a receptor 1 (C5aR1) expression using gene profiling and survival analysis. GBM tumorspheres were cultured in C5a-enriched conditioned medium (CM) from tMSLCs to induce tumor stimulation. We evaluated proliferation, invasion, and stemness of GBM tumorspheres using WST/ATP, matrigel invasion assay, and limiting dilution assays. Results were validated via western blotting and RNA sequencing. Additionally, findings were corroborated in an in vivo xenograft mouse model. High C5aR1 expression correlated with increased TME, inflammation-related gene expression, and poorer patient outcomes. CM treatment increased GBM tumorsphere proliferation, invasion, and stemness, which were reversed by W54011. CM also induced the epithelial-mesenchymal transition, whereas W54011 restored spherical morphology and induced apoptosis. In xenograft models, CM-treated GBM tumorspheres led to larger tumors and decreased survival, whereas W54011 decreased tumor size and improved survival. This study suggests a potential role for C5a in GBM progression and supports further investigation of W54011 as a therapeutic candidate.TRUEsciescopu
Metallicity and anomalous Hall effect in epitaxially strained, atomically thin RuO2 films
No full textThe anomalous Hall effect (AHE), a hallmark of time-reversal symmetry breaking, has been reported in rutile RuO2, a debated metallic altermagnetic candidate. Previously, AHE in RuO2 was observed only in strain-relaxed thick films under extremely high magnetic fields (~50 T). Yet, in ultrathin strained films with distinctive anisotropic electronic structures, there are no reports, likely due to disorder and defects suppressing metallicity thus hindering its detection. Here, we demonstrate that ultrathin, fully strained 2 nm TiO2/t nm RuO2/TiO2 (110) heterostructures, grown by hybrid molecular beam epitaxy, retain metallicity and exhibit a sizeable AHE at a significantly lower magnetic field (< 9 T). Density functional theory calculations reveal that epitaxial strain stabilizes a noncompensated magnetic ground state and reconfigures magnetic ordering in RuO2 (110) thin films. These findings establish ultrathin RuO2 as a platform for strain-engineered magnetism and underscore the transformative potential of epitaxial design in advancing spintronic technologies. Copyright © 2025 the Author(s).FALSEsciescopu
